The commercial goal of Phycotransgenics, L.L.C. is to develop economical and effective oral vaccine for animals and humans. The specific aim of this proposal is the development of a microalgal-based oral vaccine for the prevention of amebic dysentery in humans caused by the protozoan parasite Entamoeba histolytica. It is our hypothesis that an oral, microalgal-based vaccine delivery system is a cost-effective means to vaccinate against amebic dysentery. The specific objective of this SBIR Phase 1 research proposal is to determine if microalgae expressing the heavy subunit of the Gal/GaINAc lectin antigen can elicit an immune response in a model mouse system. Our strategy is to: 1) generate and confirm expression of the Gal/GalNAc lectin antigen in transgenic algae (Chlamydomonas reinhardtii); 2) use the transgenic algae expressing the Gal/GalNAc lectin antigen to deliver oral immunogens (in drinking water and/or feed) to mice in collaboration with our University of Virginia partners, and; 3) confirm induction of an immune response specific to the Gal/GalNAc lectin antigen by western blot analysis using preimmune (negative control) and immune sera from vaccinated and non-vaccinated mice. Subsequent research objectives will include pathogen challenge trials of vaccinated and non-vaccinated animals to determine whether the vaccine provides protection from the pathogen. Completion of the Phase I research objectives will provide an eventual model for investigating the delivery of microalgal oral vaccines to humans using this patent-pending microalgal-based antigen expression and delivery system.